Hydraulic torque-multiplying apparatus



July 30, 1935. A. G. RAYBURN 4 HYDRAULIC TORQUE MULTIPLYING APPARATUS Filed Dec. 2, 1929 '7 sheets-sheet 1 July 30, 1935. A A. G. RAYBURN 2,009,905

I HYDRAULIC TORQUE MULTIPLYING APPARATUS Filed nec. 2, 1929 v sheets-'sheet `2 HYDRAULIC TORQUE MULTIPLYING APPARATUS Filed Dec.2, 1929 7 Sheets-Sheet 3 sa? 24 www July' 30, 1935. A. G. RAYBURN 2,009,906 I HYDRAULIC TORQUE MULTIPLYING APPARATUS Filed Dec. 2, 1929 7 sheets-sheet 4 July 30, 1935. l A. G. RAYBURN'. 2,009,906 l YDRAULIC lTQRQUE MULTIPLYING APPARATUS 7 Sheets-Sheet 5 i Filed D66. 2', 1929 @wwmmwv Ju'ly 3o, 1935.

HYDRAULIC TORQUE MULTIPLYING APPARATUS' A. G. RAYBURN v V2,(3 09,906

July 30, 1935 A. G. RWBURNI 2,009,906

HYDRAULIC TORQUE MULTIPLYING APPARATUS Filed D60. 2.1929 7 SheBtS-Sh6et 7 www;

Patented July 30, 1935 UNITED STATES HYDRAULIC TORQUE-MULTIPLYING APPARATUS Alden G. Rayburn, Sausalito, Calif., assignor, by mesne assignments, to Automotive Engineering Corporation, a corporation of Delaware Application December 2,

1929, Serin No. 411,191

22 Claims. (Cl. 60--5 3) This invention relates to power transmitting apparatus and more particularly to hydraulic torque multiplying and speed changing devices.

The preferred embodiments of the invention hereinafter disclosed are of the type in which fluid is circulated between a pump and a motor, where maximum pumping causes maximum torque multiplication and where the fluid is at rest when the mechanism is in direct couple with the driving and driven shafts rotating at the same speed.

In the development of these preferred embodiments, special types of pumps, motors, balancing devices, centrifugally actuated thrust assemblies,

and control arrangements have been devised, the

l5 principles of which are applicable in various relations independent of those hereinafter set forth, and it is to be understood that the use of such features in other relations is contemplated as within the scope of the present invention.

'20 The apparatus ofv this invention, although adaptable to numerous uses, has been particularly designed to meet the requirements of a transmission for use with modern high speed automobile engines. Such a transmission must be capable of r safely transmitting torque at engine speeds in excess of 2500 R. P. M., its size, weight and cost must compare favorably with those of the mechanical gear units at present in use, and it must require infrequent inspection and repair. The all-rotary type of hydraulic transmission is apparently the only one that has all of these essential qualifications. However, due to temperature changes and wear in such a job, the elements mounted on the driven shaft must be separable to permit expan- 3" sion and contraction thereof, and yet must have their running surfaces maintained in fluid sealing relationship at all times. When the elements are floated together in separable relation, the pump pressures developed react to cause undesirable separation thereof to break the fluid seals, thus reducing efficiency and permitting entrainment of air and emulsication of the operating fluid. This problem I have heretofore solved by adding a balancing chamber under developed purnp pressures and lso proportioned with respect to the transmission surfaces, against which the pressure fluid reacts, that the elements are maintained, in fluid sealing engagement with each other. There are, however, further difficulties which are not disposed of by said balancing chamber as will be seen from the following explanation.

In addition to direct uid pressure reactions, centrifugal action must be considered. vThe oil or other fluid tends to flow radially outwardly as land the drivingmember of the pump,

a body and from all recesses adjacent the driven shaft during rotation of the elements mounted thereon. As the speed increases the centrifugal forces become of such enormity as to force outward radial flow of fluid between the running sur- 5 faces, with a resultant separation thereof and a consequent increased leakage. Since these centrifugalforces are not proportional to the pump pressures developed, it will be seen that a balancing Achamber of the type above discussed 10 is unable to maintain a uid seal at all speeds. Furthermore, when the apparatus is in declutched position (direct fluid circulation from one side of the pump to the other) the pressure in the balancing chamber becomes too low to be effecl5 tive.

Accordingly, it is a primary object of this invention to overcome the above difficulties. More specifically, an object of this invention is to provide means rotating at the same speed as the driven pump element and automatically adjustable, in response to centrifugal action, to urge the running surfaces of the transmission apparatus into fluid sealing engagement at all times during .operation of the vehicle. 'Ihis automatic 25 means may be utilized independently of my fluid pressure balancing chamber but I prefer to use the latter also in order to balance the reactions directly produced by developed pump pressures, whereby the added device of this invention may be more effectively utilized to overcome the separational tendencies produced by centrifugal action on the oil, and to act in declutched position when the balancing chamber has no effect. I

As already inferentially stated, a further major object of the present invention lies in the provision of a compact hydraulic transmission. unit that is light in weight, small in size, and simple in design and operation. A more specific object is to produce such a unit, operable at relatively low fluid pressures, and adapted for ready substitution, in small vehicles such as the Model VA Ford chassis, 'for the mechanical transmission and clutch at present built into these small vehicles.

A further object is to provide a flexible coupling between the flywheel of the prime mover whereby a. slight longitudinal movement of the driving and driven shaftswith respect to each other, or 50 any slight disalignment thereof, has no deleterious influence on the operation of the apparatus. This permits a slight wobbling movement of the rotating parts without binding and without material loss in efficiency.

` permit the latter to function freely,

yum une isses or the md slightly muted from the Vtaining nut shown Another object of the invention is to introduce an aligning plate between the pumping unit and a stationary portion of the motor, lwhich plate is provided with a ilat sealing surface and a spherical seating surface, whereby the pump unit is capable of limited universal movement with respect' to the motor. 'I'his feature cooperates with the flexible coupling above mentioned, to and vice versa.

A still further object is to improve the automatically variable pump and motor of United States Letters Patent 1,943,929, granted January 16, 1934 on my copending application Serial Number 380,357, filed July 23, 1929.

Another object is to provide improved means for establishing communication between the internal uid passages of the apparatusand the fluid supply reservoir.

It is also an object of this invention to equip a hydraulic transmission unit with a valve that is selectively adjustable to several positions to place the unit.in direct hydraulic lock, forward automatic, or neutral; to provide a single operating means for so positioning said valve; and to employ means that must be manipulated prior to said operating means for the valve, to predetermine the position to which the latter may be shifted.-

A further object lies in the provision of manually operable means for shifting a rotary motor from forward into reverse and vice versa, and for varying the capacity (eccentricity) of said motor. y

Other objects of the invention are such as may be attained bya utilization of the various combinations, sub-combinations and principles hereinafter set forth in the varied relations to which they are obviously applicable by those skilled in the art. s

The invention will be best understood and further objects will appear from a study of the following detailed descrlptiontaken in connection with the accompanying drawings, with the understanding, however, that the invention is not confined to any strict conformity with the showing `in the drawings, but may be changed and modified as long as such changes and modifications mark no material departure from the salient features of said invention as expressed in the appended claims. In the said drawings:-

Flgure I is a vertical sectional view taken longitudinally through one illustrated embodiment of my invention. A

Figure II represents an enlarged vertical section taken on .line Il-II of Figure I, with the rotor body and blades of the pump shown in elevation and slightly rotated from their position in Figure I.

Figure III is s vertical section 'taken on the irregular line III- III of Figure I. with the control valve shown in side elevation.

Figure IV represents a vertical section taken IV-IV of Figure I, with the rotor body motor shown in side elevation position illustrated in Figure I.

Figure V is an enlarged partial vertical section somewhat distorted, taken alongline AV--V of Figure I, with the adjacent bearing and its rein end elevation.

Figure VI is a 'plan view of theslotted cam plate that is located Just above the motor in Figure I, with the shifting lever illustrated in section to show its cooperation with the cam slot.

Figure VII shows, in side elevation, the complete assembled transmission unit of Figure I, and the controlling devices mounted thereon.

Figure VIII illustrates, somewhat diagrammatically, the complete unit of Figure I, disposed beneath the iloorboards of an automotive vehicle, with a selective manipulating device connected between the unit and the dash of the vehicle Figure IX shows, in vertical section, the apparatus of Figure I, redesigned to nt into the chassis of the present standard Model A Ford vehicle. This form, though shown as a modification, represents the preferred embodiment of my invention. The sections and controlling devices, associated with Figure I, and vshown in Figures II- VIII inclusive, are substantially the same as would be drawn with Figure IX as a base figure.

In the drawings briey described above, and in which like reference characters designate like parts, the transmission mechanism is shown com- .pletely assembled in Figures I, VIIv and Di and adapted to be mounted in any suitable manner between a source of power and a driven shaft,

with its forward (left) end arranged to be driven:

from said power source and its rear (right) end adapted to transmit multiplied torques to saidfdriven or take-oil shaft. Although the units, as shown, are disposed beneath the floorboards l i of an automotive vehicle, it will readily be under.- stood that they may be utilized in a great variety of analogous combinations. In this connection, it should also be understood that various features of construction and principles of operation of certain elements independently shown eithenwith orl without modification.

With particular reference to Figures I and VII, the housing proper for the transmission mechanism is made up of two parts, a standard bell housing I2 and a rear housing I3, with their drawn together in nuid sealing relationship by bolts Il. 'Ihe bell housing I2 is shaped to surround the pump and fluid distributing section and the rear housing il to surround the motor'. A single shaft Il is supported centrally of these housings in a manner to be described later,4 with its ends terminating adiacent the front and rear ends of the respective of housing I2 and secured thereto by bolts it. The crank shaft 2l of s. combustion engine (not shown) is disposed centrally of casing it and in alignment with transmission shaft Ii. A ywheel -22 is secured, by bolts to a ange 2l rigidly carried by said crank shaft. adaptedtodriveaportionofthepump,sswiilbe seen from the following descriptive matter.

At dlametrically opposite points the nywheel hssapairofslotsllparalleltothecrankshaft and-adapted to receive freely and carr! the heads 2t of, a pair of coupling elements 21. The bodies of these elements project radially into bearingv bushings 2l that are tightly fitted in the radial sockets 2l of an irregularly shaped reactance member Il. Ihe outer surfaces of heads Il are smoothly curved as shown, te render the driving coupling flexible to prevent binding and damage i! the axes of the flywheel and resctance member lshouldbecorne slightly disaligned ss theyrotste 'Iheflywbeelis in unhm. 'Ihe rear end of reactance member Il termiintesinanintiunedannularflangell which reacts against the outer race of one of a pair of roller bearings 88. These bearings are OPPOdtely inclined in abutting relation, supported on a sleeve 84 that surrounds the shaft I8, and their inner races are maintained in position by a nut l5 threaded on the end of shaft Il and locked thereon by a pin 88.A A cap 81, secured to reactance member 8l (as by countersunk machine screws) covers the end of the shaft and reacts against the outer race of the forward bearing. A specially shaped pump wall 88 is mounted, by virtue `of keys 88, to be rotated byV said reac' tance member and yet longitudinally slidable with respect thereto. Compression springs 4I constantly react against the reactance member 3i and tend to thrust the pump wall rearwardly.

Pump wall 88 has a cylindrical hub portion 42 upon which is mounted a forwardly inclined collar 43. This collar cooperates with reactance member 3| to form an annular chamber 44 which is.substantially triangular in cross section. A

vwedge-shaped annular ring 45 is disposed in Vchaiznber 1 4 in contact with the walls thereof.

Ring 45 is made of deformable material, such as high grade rubber, and has a Vcircular series of slots 46 cut therein to receive a plurality of hardened steel balls 41. For a complete disclosure of this device reference .should also be had to Figure V. It will be observed that, as the flywheel and reactance member rotate, the steel balls move radially outward in response to centrifugal forces, and in so doing they deform the rubber and react against reactance member 3| to wedge the collar 43 and pump wall 88 toward the right in Figure I. 'I'his action is incremented by. the outward pressure of oil against the inner wall of ring 48, such oil being fed to the space `between member. and collar 43 by way of a passage 48 that is cut through pump wall 88 into the interior of the pump.

Pump wall 88 is cored out and machined to form an annular chamber 48 which opens toward the speed responsive device just described. A ringshaped piston 5i is fitted for longitudinal reciprocation in the open side of said chamber. Portions of this piston and the reactance member 3| are extended to abut each other as at 82 in order to obtain a clearance between the pistn and the collar 48 and thus provide direct reactance for the piston against member 8|. A

ringshaped sealing leather I8 abuts the rear sideof piston 8i, being held in such relation by a series of screw -and washer assemblies 84. An annular steel ring 55 is pressed into sealing engagement with the edges of leather 53 by a set vof coil springs 88 which are compressed between said steel ring and a vertical surface of the annular chamber 49. A hole 51 extends through pump wall I8 to establish communication between chamber 48 and the high pressure side of the pump (aswill later become apparent), the resultof this being that whenever the pump is under load `it places thel oil in chamber 48 under high pressure.

This pressure reactsagainst the steel ring and leather face of piston 5I and forces pump wall 3,8 toward the right.'

A pump housing ring Y88 having a cylindrical bore is secured to pump wall 38 as by bolts 59. A iiuid distributing pump wall 6i is received within said `housing ring in spaced relation vfrom wall 8lto form a rotor chamber) and is mounted upon a radial ball bearing 82 carried by the transmissinn shaft Il. Wall 8| is caused to `rotate with wall 88 andring I8 bymeans of apair of keys 8 8 that project freely through 'slots 84 in the periphery of wall Il and tha-t to ring I8 by radial bolts 8l.

'With particular reference to Figures I and II, a pump rotor body 88 is radially mounted upon a square type universal joint for rotation with the shaft I5. 'I'he said joint. which is shown and described in 'greater detail in my above mentioned Patent No. 1,943,929, comprises a driving sleeve 61 keyed as at 88 to a reduced portion of shaft i5, with its ends abutting sleeve 34 and bearing 82 respectively, and provided with four are fixed withrespect integral enlarged portions 88 arranged in two pairs with the outer surface of each portion cylindrically curved about an axis perpendicular to that of the shaft; and a wearing strip 1| fitted upon each cylindrical portion with its outer surface flat to slidably engage the corresponding flat surface provided by a side of the substantially square hole 12 formed in the rotor body 66. This construction'permits the rotor to float freely between the pump walls and automatically prevent any rocking or cooking of the rotor which would otherwise result from such causes as deflection of shaft I5 and any minute disalignment of rotating parts.

'I'he joint is limited in width and the central side surfaces of the rotor are relieved to provide internal cylindrical chambers 13 and an outer rim 14. Radial chambers 15 reduce the weight of the parts in .such manner that fluid pressures in` chamber 15 counter-balance any reactions that tend tc force the opposite faces of rim 14 out ci sealing engagement with the respective pump side walls. lChambers 15 have a further function, to be explained later. A plurality of radial slots 16, equally spaced apart and of substantially the same width as the rotor, are formed'in the rotor body to reciprocably receive a corresponding number of rec` ngular vanes 11. Each cornerv of the inner end of each blade has-a pair of longitudinal grooves 10 in which is clipped a shoe 18, which shoe in turn rolls and slides upon the peripheral surface of a slightly resilient equalizingring 19. 'Ihere are two rings 19, one in each internal chamber 13, and they are maintained in position by the edges of shoe slots 88 which receive them. The outer ends of the vanes project through and beyond the rotor rim 14 and are compensating slippers curved to receive rockable 8|. 'I'he vane surfaces are provided Awith transverse oil grooves 81. 'I'heir edges are provided with radial oil grooves 8l. An internal radial oil conduit 84 is drilled fromthe inner end of each vane and communicates with a passage in the slipper, whereby all the blade and slipper surfaces are fully lubricated by oil fed from the center-of the rotor by centrifugalaction.

A floating control ring 88 of substantially the same width as the pump vanes receives the rotor with its cylindrical inner surface 81 slidably en- Members." containjholes 83 which reduce their gether. Asseeninl'iguren, the-controlling. Apair of vertically aligned slots lll are may be horizontally reciprocated, between cut in the outer ring, each receiving a pivot pin members Il, to vary the eccentricity (capacity) Il! tht is tted into said rlnl. Each DlvOt Dill of the pump. In the illustrated position the carries a bushing and a strong nat spring ring has been carried as rmas it can go to the H2, the latter beine so shaped and related t l iright. bringing its vertical center line to the adjacent portions of rings i2 and that it reacts position of eccentricity indicated by line Ep, thus against them with a constant tendency to thrust forcing the blades at the left side of the rotor ring 36 toward the left (Zero eCCeIltl'lCitW- into their slotsand causing, by virtue of the Diametrically opposite the ball |02 and plate equalizing rings 12, the blades' at the right to |83, control ring 8S has a cylindrical recess lll 1n assume distended positions. At this time the which freely receives the annular flange ||I of an pump capacity is maximum, but when the ring internally and (opposite) externally multiple 86 is moved to the left until its vertical center threaded sleeve H5. Aplate IIS surrounds sleeve coincides with the indicated center line of the and is secured to ring 86, by machine screws rotor assembly, it becomes concentric with shaft Ill, in such manner that flange |4 is rotatably l5 l5 and the pump capacity becomes zero. Autoheld within the recess H3. The internal spiral matic .shifting of ring 86 to vary the eccentrcity threads of sleeve ||5 engage corresponding exis obtained in a manner later to be set forth. ternal multiple threads formed on a compara- The radially disposed chambers in the rotor tively short spindle H8, which latter is immovrim, previously described, serve to maintain the ably mounted, against both rotary and reciprosides of the blades in surface engagement with catory movement, by means of`a. cap H9 that the walls of the slots in-which they reciprocate. engages o. serrated portion m of said spindle AS each blade rotates DBS the 10W pressure Slmand by means of a nut |22 threaded upon the 151011 P01125 and thereafter Places the llid ahead outer end of said spindle. The external reversed 0f it lllldel high Pressure. Slleh DI'eSSlll'e, together threads oi sleeve ||5 have twice the lead of the 25 Wlth any resiste-110e Offered t0 1058151011 DY the internal threads and are spiraled into the center Surrounding bore 31 0f the CentlfOl 11118, 110111181- of a segment |23 which is designed to counterly tendsto rock the blade slightly and throw. its balance the weight of the pump parts and iluid center line out of alignment with that of the they move away from true center, Itwm thus Slot The' extent of this movement is. 0f Comer be seen that when control ring as 1s shifted tot0 limited by the clearances between the blade and ward the right, segment |23 is carried 'an equal slot surfaces. For example, in Figure II, the distance to the left, and vice vel- A pan,- of trailing surface of that blade just encountering horizontal guiding pins |24 are can-led by ring the H-.P- Smm 9 h tendency t0 mk 0 the u with their ends siidsbly received m holes n; foto? edge as indie-ated *t r and the leading in the segment |22. These pins also prevent ro- 35 :gee 0f Said blade h tendency t0 We im tation of said segment. A pair or pins m andA e 510i "211 s t m Th n 0m! tend springs |21, similar to thou (m and im preto reduce the eilectiveness of the iluid seal bevioualy described but reacting in the apposite di- .tween lthe interior of the pump and the W01*- reotion thereto, are vertically aligned et the left ing chambers ther '1, lbut also to damage the parts as they reciprocate relative to each other' side oftigure n ua ndAsuo: said: slrmgs 1:1: o

in une contact. 'ro eliminate there disadvrmaging e segment ur e sp s tages 1 have provided the chambers 1s, the walls are of substantially the me strength d e S0 of which are reacted upon by iiuld pressure to 0mm Curved (in zero capacity position 91 the pump). when straight, as illustrated, they cause them to become sughuy distorted and are under iiexure and have stored up potential 46 radial surfaces of the slots `aretlrmly pressed energy The mass and dlspositionofthesegment |22 are into iluid sealing surface engagement withthe so e as to l I Il n I 1 J ce blades el all limethe amended eooentrio portions 0f the 11mm dially) of the slippers 12, rota arranl t auch Y 1 andaslightunlversllmovemelltofcontmlring tharearhlinlll, nlocklisprovidedwith l;

'rh nyw' reac member 2|, the um side Saus' mi an the pimp pms outsider (t: ring u and rotor blhdespiusthe exoessive weight so te as a mit in a o! the operating-duid on the right hand side, at @untelclockwise mecum (as viewed m m. any given speedof rotation. When the iiywheel ure I1). Operating iluid, preferably oil, is ted is stepped or running at low speed, eentrlfllal at low Nessun, through tm, L p passages u, force will not be great enough to overcome the .are urging the ring toward its position of consages terminate in a port 26 grooved on the centricity. At such time the capacity o! the inner face of 'said'side wall.- and a corresponding pump is aero and no fluid is received or delivered. gmovenumdedirecuyoppositeporton Howevenwhenacertainflywheelspeedisatthe other side wall. Diametrlcally oppomte the tained, predetermined by the proportioning of 00 low pressure side o! the pump the high pressure .the pump parts and spring resistances, the conside is provided with a similar pair of grooves trol ring 8i iloats eceentrlcally toward the right Sl and ll.' The oil is discharged imder pressinje Simultaneously, centrifugal force causes countert through port I2 and H. P. passagesy lli formed balancing segment |2Ito overcome springs |21 t in the rear ride nu or the pump. and move toward the left, this movement heinz u 1 The control ring il provided (see ridlt side permlttedandmeamredbytherotation ofspirali 011118.11) wiihaspherlcalballextenslon Il 2 lytlireadedsleeve Ill withinthergegmentand i that is formed on a plate |23 which is rigidly upon'the spindle lll. l'Zllie pump isthus mainsecuredtosaidrlngbymachmescrews lll. Ball tainedinambstantiallybdancedconditiomwith Il! seats in several-point contact, as at ill, withits eccmtrldty automatically governed by speed! 10 exagonll I member m thatamreodedrhrougnthewm nehmdurepumpaoutnmdmlbudnrux l ot. external housing ring 5I. This mounting l2iistightiyinsertedintherearendotbellhom- 1 ement permits horllcntal recipe-ocation in|',andisheldin insertedpositionby morne mberesistance or springs nz and m, on or which description of these will be deferred until the motor nu been described. an msning'pieee m is floated between the pump and the distributing block, being nxed against rotation by a pin I,

the oppositeends of which project loosely into` the block and plate respectively. This plate ill has a central hole itl establishing communicaltion between the low pressure pump passages Il and low pressure reservoir |2I, and a plurality of through ports ill establishing' communication between the high pressure pump passages lill and the high pressure reservoir lli. The left face of the aligning plate is flat toprovide a proper running surface for the rotating pump. and its right (rear) face is spherically curved in order that it, and the pump. may have a universal seat upon the block Ill. It will be -observed that this feature cooperates with the flexible driving coupling 25, 2C etc., each permitting the other to act without restriction, and that binding of parts and damage thereto, such as scoring caused by shaft flexure or shaft disalignment. are eliminated. v Shaft I l is journaled in stationary block in by means of a double ball bearing |31. 'I'he latter is maintained in position by an integral shoulder il! on the shaft and a sleeve |39 mounted on the shaft with its ends abutting bearings |31 and 82 respectively. The rear face of the block B28 ls flat and smooth and forms one wall of a rotary motor now to be described. v

The rotor ofthe motorlsee Figures I and IV) is of substantially the lsaine construction as that of the pump, except that it is approximately twice as wide. It'comprlses a rotor body lli having a rim portion |62 providing radial'chambers ill surrounding internal side chambers |43, and universally mounted upon a substantially square porl tion i of shaft IB by means of four wearing strips |45; and a set of radial blades i slidably mounted in slots ill in the rotor with equalizing rings H8 arranged in the chambers i to engage shoes |49 to press the blades outwardly. The hat surfaces ofthe blades have oil grooves ill, and internal oil passages. in are drilled radially through the plates to supply oil to cross passages 853 and to the blade tips. Rockable slippers lll. are mounted on thev blade tips with their outer surfaces in sliding engagement with the internal cylindrical surface ill of a' control ring IBI. which latter though differing in construction and manner of operation from the pump control ring 86, is horizontally reciprocable, like said pump ring, to vary the eccentricity (capacity).

The low pressure passages itl in the distributing block i2! terminate in a specially shaped port lill to receive fluid exhausted from the motonand the high pressure passages |32 'terminate in a similar port ill for ldelivering huid to the high pressure side of the motor. 'llhe working chambers of the motor are closed at the rear by a wail Ill that is slidably mounted on the hub portion |82 of a reactance member lli; and pressed to ward the left by circular contact with said reactance member, as at Ill. Hub portion il! is slidably keyed, as at IIS. in the rear end of housing it. and wall III isin turn prevented from rotating by a pin i the ends of which project freely into elements I II and ill respectively.

anutlllonthe'shafhandanexternallylhleaded nut Illscrewedintoanendofthehearingcale.-

Asealingalsemblyillisprenedsgaindnutl by a lock nut i'ii, relative rotation of the latter' being prevented by e eener pm m.' 'ineens erA shaft Il is splined as at Ill to drlve'thc sleeve |74 of a universal Joint. dedgnated hy numeral |15, and thence to drive a ill'ilellershaft Ill. This is a conventional arrangement. as employed, forA example, in the Model A l'iord cha-is, to drive the rear wheels of arvehicle. 'lhe end of housing il has a flange IIl to which bolts III secure apairof radiallyspacedsphericalsegments il! and Ill. A torque tube III hasa spherically curved end |82 which slidably fits hetween segments i." and Ill to permit univexaal movement of said torque tube while preventing longitudinal movement thereof. Any oil accumulating in the space surrounding universal joint IIS is permittedto drain to the lower side of the motor housing by way of a slot iil provided in housing i3 adjacent the bearing cage III.

The control ring Ill of the motor is shiftahle horizontally to vary the eccentricity, either manually-or automatically. Unlike the pump ring, it does` not rotate, and it may be shifted either to the right or left of a aero capacity position, whereby the motor is reversible. As illustrated in Figure IV it is in its extreme right hand position, with the rotor turning in the same direction as the flywheel. to drive the vehicle forward. At its upper side ring i has a flat surfaced boss I Il that slides on a corresponding surface ill of a cap i mounted in the upper side of housing i3. The lower side of ring |56 has an integral Aextension IIS which receives a horizontal flat plate |81. Spaced below this plate a closure cap i is screwed into an opening in housing il and provides a seat for the spherically curved face lll of a plate i9i. The center of curvature of face |89 is located in the axis of shaft i5 centrally of the square joint i, Between the plates ill and iii there is disposed a bearing pad il! in which are freely mounted a plurality of steel balls i which may slide and roll on the surfaces of said plates. Pad |82 has a pair of pins i disposed diar'netrlcally opposite each other at equal distances from the vertical center line of the rotor,

one of these pins projecting upwardlyinto a hole in plate |61, and the other projecting downwardly with a loose ilt into a hole in plate iIi. This permits an anti-frictional gyratory movement of the balls when the control ring is shifted horizontally while being supported and guided between the devices above described.

It will readily be understood that such a supporting and guiding means as this may be lubstituted for that shown at the bottom of the pump control ring Il. g

At its right side (Figure IV) control ring il! has securedthereto, by screws ill, a plate i which carries several horizontally projecting fingers III. A heavy compression spring III. is coiled around these fingers with one end reacting lagaimi: plate I and its other end-reacting against the inside surface of a closure cap ill that is secured to housing i3 by boltslli. Spring I constantly vurges the control. ring toward its concentric pilition. 'lhefingcrs ill aresupportedandguided on an anti-frictionbearing member Il! tint is carriedbythcbali'enditlofaspindieldtthe in response to the torque ltricity of the motor shaft |12. Any further moveillustrated described, i'ormed thereon a cup-shaped index' 222 having an internal working .chamber 221. A piston 222 tits within chamber 221 and is stationarily supported by a piston rod 222 the outer end of. which is secured by a nut 2|| to a closure cap 2|2, the latter in turn being secured to housing |2 by means of bolts 2|2. A pair of intersecting passages 2 Il and 2 I5 have their ends open to chamber 201 and the high pressure side of the motor respectively, thus establishing constant communication between said chamber and said high pressure side. The intersecting ends of these passages, necessarily opened to the control ring surface during the drilling operation, are closed by plugs of any suitable material, as indicated at 2|6, to prevent leakage into the space developed pump pressure exceeds a 'predetermined value, which DiS- ton 222 and the resistance of spring |22, upon the right hand face of piston 222 been transmitted thereto via the high pressure side of the motor and the passages 2li, 2|!) and forces the cylinder 222 and control ring l|52 toward the right. This produces a and renders it operativeto drive the propeller ment of the control -ring to right'or left is dependent upon iiuid pressures and, since the latter are proportionate to the resistance of the propeller shaftl to rotation, it will be seen that the capacity of the motor is automatically variable demands imposed by the driven wheels of the vehicle.

During the time that the motor is permitted to operate as above described, it is in what may be termed its Forward automatic position. Bince the pump and motor may be run at diilerent elective speeds,land since, the eccentricity of the pump being the pump may be near its zero capacity and delivering a very small quantity of iluid to the motor when the latter, which is larger than the pump, is in its position of maximum capacity, 'the relative capacity of the motor may become as great as three hundred times the capacity oi the pump at a given instant. It follows that the motor may drive the propeller shaft at one three hundredth of the flywheel speed, substantially no slip in my torque multiplication ratio of approximately 300:1 may be obtained.`

The motor control ring |22 is subject to manual, as well as automatic control. A bracket 2|1 the cap |22 at the top of the 'motor'. with a cam plate 2|2 therebetween. an secured to housing I2 by bolts 212. Bracket 2|1 has a socket portion 22| which receives the ball 222 of a shifting lever 222, said ball beingl retained in place by a nut.22l 'and housed by a spherical cap 222. Ball 222 rigidly carries a downwardly projecting shifting extension 222, the lower end 221 of which is ball-shaped and `adapted to slide in an arcuate groove 222 cut in the control ring about a center located within ball 222.4 In the lower surface of groove 222 otr 222 and 22| eachof which is adapted to 4receive and yieldably retain abail 222 that may be positioned. upon shifting vthe lever to proper positions-to be snapped downwardly into said recesses by a compression spring -motor and propeller shaft and hence 222 carried within the end 221 of the shifting extension 226. These devices are used to locate certain positions o1 the shifting lever and to resiliently latch it in such positions, as will now appear. g

An irregular cam slot 222 of special shape is out in the cam plate 2|.2 to act as a guiding, positioning and limiting means ior the extension 226 o! the shifting lever. With particular reference to' Figure VI, the extension 222 is shown at that one of its extreme lateral positions in which its center line passes through a point indicated as Maximum capacity which position corresponds with those o! the motor parts as illustrated in Figures I and IV, with the ball 222 latched in recess 229. 1f the lever is shifted laterally to move extension 222 toward the indicated Zero capacity position, the ball 232 remains in recess 229 and forces control ring |56 into concentricity with the motor rotor and shaft l5. To reverse the motor, lever 222 is shifted thus moving extension until it engages edge 225 of the guided laterally and forced rearindicated in Figure VI as Reverse, at which time the control ring |56 of the motor has reached its extreme left hand positionoi eccentricity. During this movement the ball 222 has popped out. dropped into recess 22|. The edge 222 of the cam slot now abuts one side of extension 226 and prevents theautomatic motor control mechanism from shifting .the control ring whilevinv reverse.

During normal forward running, however, the cam slot permits the extension 222 to play back and forth laterally, between the Zero capacity" and Maximum capacity" positions in response to the action of the automatic control mechanism. It it is desired to use the transmission u nit as a vehicle brake, as when traveling down hill, at which time the capacity of the motor is at or near Arsero because the vehicle wheels and propeller shaft have a tendency to travel faster than the flywheel, it is only necessary to pull backward gradually on shifting lever 222. extension 220 to move forwardly along a cam slot edge 221 that is so inclined as to simultaneously shiit the extension laterally toward a point marked Maximum braking. At this time the motor is approaching maximum capacity and actto supply more iluidto the pump proper (which now acts as a motor) than said pump proper can normally handle. 'This produces an enormous resistance to rotation of the brakes the vehicle. To coast with practically no resistance the pump is allowed to go to zero capacity, and themotor also, at which point no fluid flows and d the parts are all in balance and free to rotate at high speeds. y

During all o! the preceding descriptions and assumed that the distributing es |22 have been opn to establish pressure reservoir the control of the operator are provided for completely closing passages |22 or interconnecting them directly with the low presir |22, as follows:

I ticular reference to Figures I and block |22 is so cast as to provide a valve housing 222 interrupting the H. P. passages |22. A pair of short-circuiting passsses 222 are formed in block |22 to establish of recess 222 and 4 inlet side of the motor. However,

. fluid and as a result its rotor and housing are hydraulically locked together for rotation as a communication between the L. P. reservoir |29 and the interior of said valve housing. A liner 24| is inserted in the valve housing to form a valve chamber proper, said liner being provided with ports 242, 243 and 244 for connecting the valve chamber with the H. P. passages |32, and the L. P. short-circuiting passages 239, respectively. The liner has a tight fit and is maintained in position by an end plug 245 and an end cap 246 which screw into housing I2 to abut the ends of said liner.

A cylindrical oscillating'valve 241 is mounted in liner 24|. This valve is provided with a central bore 248, closed by an end plug 249, a narrow elongated port 25|, and a wide elongated port 252. When the valve is in the position illustrated, its port 25| establishes communica- Ation between its central bore 248 and the H. P.

chamber 63|, with its port 252 connecting said central bore with the H. P. passages |32 that lead into the motor. At this time the shortcircuiting passages are blanked off, and the transmission is operating in Forward automatic. If the valve is oscillated clockwise in Figure rI until its port 25| overlaps the liner ports 242 and 244 the circulating iiuid is short-circuited between the H. P. and L. P. reservoirs with the result that no operating pressures of sufficient magnitude to drive-the motor are transmitted thereto. This position may be termed Declutching and it isto be utilized prior to manipulation of the shifting lever to secure reversal or to multiply torque at the will of the operator. If the valve is oscillated in the opposite direction, past the illustrated position, until ports 242 and 248 pass totally out of communication and the former is blanked by the valve surface, the pump has no place to deliver high pressure unit to drive the driven shaft I5 independently of the motor. lThis position of operation, which is highly desirable after a relatively high vehicle speed has been obtained as-when driving on interurban highways and country roads may be aptly designated as High. In such position the motor is wholly under low pressure and doing no work, the bearing |65 increases .its loadcarrying capacity and the fluid, not circulating, is given an opportunity to become cooled.

In order that the valve may be properly inserted and its actuating mechanism properly assembled, I provide recesses 253 in the liner at predetermined points (see Figure III) and, in a transverse passage 254 in the valve, I arrange a compression spring 255 for snapping portions of locating balls 256 into said recesses as the valve is oscillated to the position illustrated. To prevent any fluid leaking into the chambers at the ends of the valve from building up pressures therein, a port 240 is provided near the right end of liner 24| (see Figure III) which Apermits fluid to escape to the outer surface of the liner andv thence to thespace Within housing i2 by way oi' a longitudinal groove 250 cut on the surface of the block |28. A similar groove 268 is provided at the left end of the valve but a port corn responding to port 240 is unnecessary vbecause of the presence ci the holes 253.

With reference to'Figures III, IV, and VII, one end of the valve 241 is provided with an integral stem 251 journaled in a. bearing 258 within the end cap 246, said stem having a serrated portion 268 receiving an actuating sleeve 26|. that is held in position by a nut 262. Sleeve 26| has a toothed segment 268 in cooperative engagement with the teeth 264 of another segment 265, the latter constitutingv an extension of a manually oscillatable plate 266. The plate 266 has a sleeve portion 261 journaled on a horizontal spindle 268 that is rigidly supported by the transmission housing. A foot brake lever 269 has its hub portion 21| freely fulcrumed on the sleeve of said plate, and the hub 212 of av foot operated lever 213 (corresponding to the conventional clutch pedal lever) is keyed as at 214 upon the outer end of sleeve 261'. A nut and washer assembly 215 maintains the hubs and sleeve in position upon the spindle. Lever 213 carries a shank 216 connected to a foot pedal (not shown). When the latter, is depressed, the lever 213 is voscillated to oscillate sleeve 261 andplate 266, the segment 265 of which in 'turn actuates the valve sleeve 26|. It will thus be seen that the valve 241 is oscillated, the extent of its movement being dependent upon the distance through which the foot pedal is depressed. A tension spring 211 acts upon an arm 218 carried by plate 266, (see Figure VII) constantly urging the valve and its loperating mechanism in a direction reverse to that The plate 266 (see Figure VII) has an upstanding lug 219 in which are cut three stepped notches vdesignated from left to right as Hydraulic lock,

--Forward automatic and Neutral respectively. Directly above this lug a small casing 28| is secured to the main transmission. housing, which casing is open from top to bottom to receive a vertical reciprocating plunger 282. This plunger at itsv lower end carries anintegral latching member 283 that is adapted to 'be raised or lowered to cooperate with any one of the three notches above described. A recess 284 is cut in the outer surface of plunger 282 to receive an eccentric cam 285 formed on one end of an actuating shaft 286. 'I'his shaft is journaled in a cap 281 with its outer end clamped within and adapted to be oscillated by a control arm 288. Oscillation 'of said arm causes the eccentric cam to engage the recessed portion of the plunger to reciprocate the latter. A link 289 (see'Flgure VIII) has one end pivotally connected to arm 288 and the other freely pivoted tothe lower end of a bell crank 29|, which latter is freely fulcrumed at 282 upon a. stationary frame member 293. The dashboard 294 of the vehicle supports a small casing 295 through which and the dash a control rod 296 is adapted to slide. The lower end of rod 296'.is p ivotally connected to the upper end of bell crank 29| and the upper end carries a knob 291 that may be manipulated by the driver to reciprocate said rod. There are three peripheral grooves cut on rod 296, these being designated as Hydraulic lock, Forward automatic and Neutral respectively, and being adapted to yieldably receive the end of a small plunger 298 which is slidably mounted in casing 295 and pressed downwardly by a coil spring 299. The mechanisms justy described are vso coordinated during assembly that, with the lug in a clockwise dlrec- 76I 8 tion. If knob 291 should now be pulled outward- 'ly until plunger 298 engaged with the lowermost groove on rod 296, the latch 283 would be lifted suiiciently to permit it to engage the foremost notch in lug 219 (as spring 211 oscillated the latter) and the unit would then be operating in Hydraulic lock or High. Upon complete depression of the foot pedal at any time, followed by pushing knob 291 down against the dash, the llatch 283 would assume a position within the Neutral notch while the valve 241 would interconnect botn sides of the pump and allow the capacity to become zero.

With reference to Figures I and III, a iluid reservoir 30| is formed in the housing I2 just above the fluid distributing block. 'I'his reservoir is closed by a cover plate 302 having a conduit 303 through which operating fluid may be supplied from any convenient source at atmospheric pressure. A hole 304 (Figure I) establishes communication between the reservoir 30| and the L. P. passages |30, which hole has threaded therein a Ivalve assembly comprising a cage 305, a ball 306 and an upper hollow plug 301 providing a seat for the ball. Several ports 308 are provided in the bottom of the cage in order that the ball may normally rest thereon under the action of gravity without disrupting communication between the reservoir and L. P. passages. Any air entrained in the fluid circulating system may escape through this valve assembly but, should the pressure in the L. P. passages suddenly rise from any cause, the oil therein would hurl the ball 306 upwardly against its seat on plug 301 and thereby prevent escape of the operating oil fromthe system.

Referring again to Figures I and III, a pair of cages 309 and 3II, similar to cage 305, are screwed from the reservoir 30| into the H. P. reservoir |3| of the distributing block |28. Cage 309 receives a plug 3I2 having a hole 3|3 therein normally closed by a ball 3I4 and a relatively light compression spring 3|5. There is a hole SI5 in the bottom of the cage. Should the H. P. reservoir, for any reason whatsoever, suddenly have its pressure rendered sub-atmospheric, the ball 3|4 would immediately be drawn down olf its seat to permit oil from reservoir 30| to enter the H. P. reservoir and eliminate such sub-atmospheric condition. The cage 3II threadedly receives a small upright casing 3I1 which has a number of relief holes 3I8 around its periphery. These holes open into a hollow interior which in turn communicates with H. l?. reservoir by way of cage 3|I and a hole 3|@ in the bottom of said cage. A ball 32S normally closes hole 3I9, being urged thereagainst by a coil spring 322. The compression of said spring may be varied by a stem 323 screwed into casing 3I`l and 'locked in position by a-nut 320. This valve assembly, as will be obvious, forms a safety valve to permit escape of oil from the H. P. reservoir to the atmospheric reservoir 30I whenever a predetermined maximum pressure is developed in the former.

A pipe 325 (see Figure III) delivers a cooling medium to prevent overheating oi the transmission during operation, this medium being circulated through chambers 326 which are formed in housing I2 about the distributing block I28, after which it exits through a pipe 321.

A pipe coupling 328 is screwed into the bottom part'of housing I2 adjacent the flywheel to draw off any leakage fluid from the circulating system. This fluid may be returned through conduit 829 to the fluid reservoir 30| by any suitable means (not shown). An annular piece 4oi sheet metal 33|, secured within the housing I2 by screws 382 and surrounding a portion of the ilywheel prevents access of this leakage fluid to the ilywheel `casing I6.

The modified form of hydraulic transmission unit illustrated in Figure IX diifers in but few respects from that above described. It has been specially designed and proportioned so that it is compact and of a size to permit its substitution in the present Model A Ford chassis for the comparatively unsatisfactory mechanical unit now employed therein. In Figure IX, the housing sections I2', I3', and I6 are of different shapes than those, I2, I3 and I5 of the other figures. Section I2 does not house the distributing block |28' but abuts the forward face thereof. Block |28' provides its own housing, withV the upper reservoir 30| formed therein, whereby the unit may be conveniently assembled and disassembled. In order to shorten the unit, ball bearings 33 and |65 are substituted for the roller bearings 33 and |65, the rotor |4I of the motor has been narrowed, the width of block |28' is decreased with respect to block |28, and the sleeve 34 and nut 35 have been combined to form a shorter integral sleeve and nut 34' in Figure IX. The latter feature permits a attened closure plate 31' to be used adjacent the flywheel.v The plate 31' is provided with a central ball-shaped extension 333 that is piloted in the ilywheel 22' by a bearing 334.

The wall 38 and ring housing 58 of Figure I have been reshaped and integrally combined as a single element 38' in Figure IX, which element is equipped with a peripheral set of external gear teeth 335 engaging an internal gear 336. An annular sheet 331 of pliant and flexible material is riveted to gear 33B as at 338 and secured to the ywheel 22 by an engaging ring 339 and bolts 34. The outer pump housing is thus driven flexibly and directly from the flywheel and in turn drives reactance member 3|', whereasin Figure I, the reactance member 3| was coupled to the ilywheel to drive the pump wall.

With further reference to Figure IX, the head 302 and bolt 343 mounted in the bottom of casing I2' are provided Afor cooperation with the standard Ford radius rod (not shown). A small plate 344 is secured to the lower left face of block |28 and engages the aligning plate |33 to prevent rotation of the latter. The extension 226 of motor shifting lever |23 carries a plunger 335, pressed downwardly by a spring 233' and having a pointed end for engagement with receases 340 in the motor. An integral cam plate formation 2I8' takes the place of the separate plate 2I8 vpreviously described and a slot 234', similar in shape to slot 234 of Figure VI, is provided therein.

' An adjusting means, not shown in .Figure I, is provided in the rear end of the unit of Figure IX. The rear wall 59 of the motor is provided with a recess 350 which receives one end of a spindle 3431 that is journalled through housing section i3' and provided at its other (projecting) end with a square head 348. This spindle has a pinion 349 fixed thereon and in driving engagement with the rim of a reactance member I6 I the latter being journaled within, and longitudinally slidable with respect to, the motor wall |59'. The reactance member IBI' is threaded, as at 35|. upon a bearing cage |62 that is prevented from rotating by a key |63'. 4 It will thus be seen that spindle 341 and pinion 343 may be adjustably turned to rotate ractance member |6l' and that such rotation causes the latter to move longitudinally to vary its reactance, at |60', against the motor wall |59'. This adjustment is utilized to'take up any play of the balls 41 of the centrifugal balancing device and to draw all vertical running surfaces of the apparatus into proper initial engagement. A lock nut 352 on spindle 3H is provided to prevent accidental l@ movement of the adjusting mechanism.

Any other elements which correspond in function with those of Figure I but have been slightly altered structurally, are designated with primed numerals in Figure IX.

Operation Although the operation of the apparatus has been set forth in ydetail in connection with the description of the several portions thereof, a brief rsum of the method of operation will be given Vat this point.

To illl the apparatus an operating fluid, preferably oil, is fed into the upper reservoir (or Sl) with the pump slowly rotating to receive the oil from the L'. P. reservoir and pass it .into the H. P. reservoir. All of the various passages and recesses become filled and any entrained air y gradually expelled through valve cage holes 308 during this operation. Fluid passes into the motor chambers, and at this stage it is well to rotate the motor slowly, as can readily-be done by jacking up one of the rear wheels of the vehicle. The operating oil surrounds lthe shaft from the forward cap 3'! (or 37') to the rear sealing assembly |69 (or |59'). When all of the internal passages, recesses and reservoirs have been completely filled the apparatus is ready for use as a torque multiplier.

The driver starts the vehicle engine with the latter throttled low so that, as its flywheel drives the pump housing, the control ring 8i of the pump is rotated so slowly that it remains concentric with shaft |5 With no tendency to rotate the same. The valve 241 at this time should have been in its "Neutral position but no harm is done if it had been in Forward automatic instead, because unless the driver raced his engine in the latter position to cause an automatic assumption of eccentricity by the pump and consequent developed pressures, the motor would not ing mechanism set f or Forward automatic ration and the vehicle brakes released, the drlver'accelerates the engine, as a result of which the pump/automatically assumes a working posi- -tion and develops pressures which, as soon as they become great enough in the control cylinder 20S to overcome the resistance of spring |98 (Fig. IV), thrust the motor control ring to the right, giving it a large eccentricity and thereby causing it to drive the shaft I5 and start the vehicle in motion. As the vehicle picks up speed and the torque requirements become less, the pressure in control cylinder 286 decreases, as does also the motor eccentricity (capacity with the result that the motor rotor rotates faster and more closely approaches the speed of the flywheel and pump housing. When the engine speed reaches about 1060-120@ R. P. M. centrifugal 'force causes the pump blades and ring 86 to extend their greatest, and the motor blades and ring 458 due to vehicle speed, become concentric with shaft i5. Since the motor does not in this condition receive any iluid the pump is no longer l5 able to deliver its full capacity to the motor,

je driven the rear wheels. Now with the conand the fluidl back pressures cause the pump housing and rotor to be'hydraulically, locked tol gether. all engine torque thereby being transmit-- ted through said rotor -directly to shaft l5. At this time the driver may manipulate the control mechanism to shift valve 2H into its "High or Hydraulic lock position, whereupon the unit is forced to continue in direct drive with its parts in the positions just described.

If the driver wishes to coast or to stop the vehicle, he may shift valve 241 to its Neutral position.. If, after comingto a stop, he desires to back up, he may move valvev 241 into the same position utilized for Forward automatic,

at the same time manipulating shifting lever Reverse position indicated in 223 to secure the Figure VI. Further modes of manual operation of the motor control ring |56 have previously been `explained and no repetition here .should be necessary.

Having described l certain preferred `embodiments of my invention with the particularity required by law, what is desired to be secured by Letters Patent and claimed as new is:-

l. A hydraulic torque-multiplying transmission unit comprising a driving member; a driven.

shaft; a pump mounted on said shaft and actuated by the relative rotation of said member and said shaft; means automatically varying the capacity of said pump in response to the rotative Aspeed of said driving member; a motor mounted on said driven shaft to drive the same;means for distributing operating fluid between said pump and said motor; and means automatically varying the capacity of said motor` in response to the torque demands of said driven shaft.

2. In the apparatus defined in claim 1, said apparatus having' several separable running surfaces substantially normal to said driveni shaft; a reactance member'secured to said shaft and remote from the pump; a second reactance member secured to said vshaft adjacent that side of the pump which is more remote from the motor; and means, disposed between said pump and said second reactance member, operable to prevent separation oi' said separable running surfaces, said means being automatic in response to reactances developed as the. pump is driven by said driving member.

3. A hydraulic transmission apparatus comprising, in combination, a driving member;v a driven shaft; a pump consisting of a housing 40' .engaging that side of the motor which is more portion having a flexible drive connection with said driving member and a complementa] rotor portion having a flexible driving connection with said shaft; a motor for driving said shaft; a uid distributing block mounted between said pump and said motor;. and an aligning plate disposed between said pump and said block having a spherical seat upon one of them and a :dat running surface engaging the other, whereby said pump is permitted a slight universal rocking movement with respect to said block.

4. In a hydraulic transmission apparatus, a shaft; a huid circulating unit comprising a pump, a distributing means and a motor mount ed in heating engagement with each other. in the order named, upon said shaft; driving means in engagement with a portion of said pump; and means, automatically operable in response to the speed of rotation or" said driving means, cooperating with said shaft and said unit to force said pump, distributing means and-motor into iluid sealing engagement.y

' means adjacent one of said 5. In combination in a hydraulic transmission, a stationary casing; a shaft journaled in said casing; a power transmitting device mounted upon said shaft and having a plurality of charnbers for receiving and expelling fluid, said power transmitting device embodying'a surface to be maintained in fluid-sealing engagement with a portion of said stationary casing; and means, automatically operable upon rotation of. said shaft, associated with said power transmitting device to maintain said fluid-sealing engagement.

6. In sub-combination, a rotary power transmitting device having a plurality of .chambers for receiving and e'rpelling fluid, said device including a ported wall for distributing said fluid; a member substantially iixed against relative movement longitudinally of the axis of rotation of said device; and centrifugally actuated means for thrusting said ported Wall into fluid-sealing contact with said member.,

'7. In sub-combination, a shaft; a rotor mounted on said shaft; a pair of substantially parallel side walls, one at each side of said rotor; means substantially restraining one of said side walls against longitudinal movement with respect to said shaft; and balancing means connected between the other of said walls and said shaft, said balancing means including a device automatically operable, in response to rotation of said shaft, to force said walls into :duid-sealing contact with the sides of said rotor.

8. In sub-combination, a rotary shaft; a pair of radial members mounted adjacent each other on said shaft, one secured against longitudinal movement with respect to said shaft and the other shiftable longitudinally of said shaft, whereby the said members cooperate to form'in effect an expansible radial chamber; means abutting one of said members and providing a pair of surfaces to be sealed against fluid leakage; and a relatively heavy substance within said chamber whereby, when said shaft is rotated, said substance flows outwardly in said chamber by centrifugal force with a tendency to expand said chamber Vthereby separating said radial members and effectively sealing said surfaces.

9. In the apparatus donned in claim 8, said heavy substance comprising a ring, made oi deformable loaded material, and saidA chamber being wedge-shaped in cross-section.

10. In sub-combination, a rotary shaft; a pair of radial members mounted adjacent each other upon said shaft, one of lthem secured against longitudinal movement with respect to said shaft, and the other shiftable longitudinally of said shaft, whereby -the said members cooperate to form in eiect an expansible radial chamber;

membersl and providing a. [pair of surfaces to be thrust into close surface engagement upon expansion of said radial chamber; and a relatively heavy substance within said chamber whereby. when said shaft is rotated, said substance ows outwardly in said chamber by centrifugal force with a tendency to expand said chamber thereby separating said intol radial members and thrusting said surfaces engagement 11. In a hydraulic transmission apparatus, a stationary casing; ing; a power transmitting device mounted upon said shaft and having a plurality of -high and low pressure uid chambers, said power transmitting device embodying a surface to be maintained in uid-sealing contact with a portion of said stationary casing; -a reactance member substana shaft journaled in said cas-- tially immovably mounted against longitudinal movement with respect to said shaft; a hydraulic balancing device arranged between said reactance member and said power transmitting device, said balancing device including an expansible chamber in communication with one of said high pressure chambers; and means, operable by centrifugal force, associated with said power transmitting device to cooperate with said hydraulic balancing device in maintaining said Y* luid-sealing Contact at all times during operaion.

12. In a hydraulic transmission apparatus, a stationary casing; a shaft journaled in said oasing; a power transmitting device mounted upon said shaft and having a plurality of high and low pressure fluid chambers, said power transmitting device embodying a surface to be maintained in uid-sealing contact with a portion of said stationary casing; a rcactance member substantially immovably mounted against longitudinal movement with respect to said shaft and cooperating with said power transmitting device to form a radial chamber; a relatively heavy deformable ring disposed within said chamber and adapted to be forced radially outwardly in response to centrifugal action, thereby to thrust said device away from said reactance member to maintain said fluid-sealing contact; and means to boost the outward expansion of said ring, comprising a fluid passage open at one end to the inner surface of said ring and in communication at its other end with the fluid in the interior of said power transmitting device.

13. A hydraulic torque-multiplying transmission unit comprising a driving member; a driven shaft; a pump driven by said driving member; a motor driving said driven shaft; means for distributing operating fluid between said pump and said'motor; said unit having several separable running surfaces substantially normal to the axis of said shaft; a pair of reactance members, one adjacent that'side of the motor which is more remote from the pump and the other adjacent that side of the pump which is more remote from the motor; and means, disposed between said pump and said other reactance member, operable to prevent separation of saidseparable running surfaces, said means being automatically actuated in response to the speed of rotation of said driving member,

i4. A hydraulic transmission apparatus comprising a driving member and a driven shaft; a pump engaged by said driving member; a motor for driving said shaft; high and low pressure passages for distributing fluid between said pump and said motor; a uid reservoir containing low pressure iiuid, disposed adjacent said block; a normally open check valve establishing communication between said reserlvoir and said low pressure passages; a second check valve normally closed by a spring that yields for establishing communication between said reservoir and said high pressure passages whenever the iiuid pressure in the latter descends below a predetermined value; and a relier valve for preventing the attainment of abnormally high pressures in said high pressure passage.

i5. A hydraulic transmission apparatus comprising a driving member and a driven shaft; a pump engaged by said driving member; a motor for driving said shaft; a block provided with lon gitudinally arranged high and low pressure passages for distributing uid between said pump and a block provided withsaid motor; and a valve assembly mounted in said block to intersect a high pressure passage, said assembly including a' single portedvalve, disposed transversely and adjustable at will. to selectively open said high pressure passage, close said passage, or establish communication between said passage and a low pressure passage.

16. In a hydraulic transmission unit, a pump; means for driving said pump; a motor; means driven by said motor; a valve system forcontrolling the distribution of fluid between said pump and said motor, saldsystem including a manually operable valve for controlling the paths of fluid flow; means for manually operating said valve; a valve position selecting mechanism; and means rendering the manipulation of said operating means dependent upon prior manipulation of said selecting mechanism.

17. In a hydraulic transmission apparatus, a pump, means for driving said pump; a motor; means driven by said motor; and means for distributing fiuid between said pump and said motor; said pump and said motor each comprising a rotor mounted on a fixed axis and housed within a control ring to form therewith working chambers, said control ring being laterally adjustable to a plurality of positions of eccentricity with paratus comprising a set of complemental de-v A vices forming chambers for receiving and discharging fiuid during operation; a power shaft in driving said last mentioned device 'being centrifugally operable in response to its own speeds of rotation, for automatically varying the capacity of the apparatus.

-20. In a hydraulic transmission, a fluid pump; a fluid motor; and means for distributing fluid between said pump and said motor; said distributing means comprising means providing concentrically arranged high and low pressure fluid chambers of almost completely annular shape in communication with the pump and motor, a valve casing overlapping said high and low pressure chambers and ported for communication therewith, and a ported valve fitted within said casing to control the flow of fluid through the latter.

21. In the combination defined in claim 20, said high and low pressure chambers surrounding the axis of the transmission in annular relationship, and said valve being transversely mounted and designed for selectively interconnecting the chambers, or stopping the fluid' circulation or causing the fluid to circulate in separate high and low pressure paths.

22. In a hydraulic transmission apparatus, a driving member; a driven shaft; a pair of power transmitting devices comprising a fluid pump and a fiuid motor mounted in alignment'and having drive connections with said member and shaft respectively, one of said drive connections being flexible to permit one of said devices to be slightly shiftable universally relative to the axis of alignment; a stationary distributing block` disposed between said pump and said` motor; and a ported distributing plate mounted in fluid sealing engagement with said block and one of said devices and shaped to cause limited universal adjustment of the latter relative to said block.

ALDEN G. RAYBURN.

connection with one of said devices;l 

